Photographic developer compositions

ABSTRACT

Aqueous dispersions of benzyl alcohol can be formed with emulsifying agents such as hydroxyethyl cellulose. Such dispersions are highly effective in forming photographic processing solutions.

United States Patent 72] Inventors Roy Jones Kanous Hilton; Henry JosefFassbender, Rochester, both of N.Y. [21] App]. N 0. 702,205 [22] FiledFeb. 1, 1968 [45] Patented Oct. 26, 1971 [73] Assignee Eastman KodakCompany Rochester, N.Y.

[54] PHOTOGRAPHIC DEVELOPER COMPOSITIONS 3 Claims, No Drawings [52] US.Cl 96/55, 96/29, 96/66.l [51] Int. Cl. G03c 7/00 ['50] Field of Search..96/55, 66.1, 29

[56] References Cited UNITED STATES PATENTS 2,945,761 7/1960 Weissberger96/55 3,364,025 1/1968 Becker 96/29 FOREIGN PATENTS 4/1952 Great BritainOTHER REFERENCES Primary ExaminerNorman G. Torchin Assistant ExaminerWon H. Louie, Jr. Attorneys-W. O. Hodsdon, P. R. Holmes and D. J.Holter ABSTRACT: Aqueous dispersions of benzyl alcohol can be formedwith emulsifying agents such as hydroxyethyl cellulose. Such dispersionsare highly effective in forming photographic processing solutions.

PHOTOGRAYHIC DEVELOPER COMPOSITIONS This invention relates tophotographic processing solutions. In one aspect this invention relatesto photographic color developers and processes used in the productionthereof, especially wherein the color developer components areprepackaged in solution form for ready mixing and use by the trade.

In the processing of photographic film and paper, wide varieties andlarge quantities of photographic developers are utilized. To facilitatethe preparation and use of these developers, it has been found desirableto package the developers in liquid form usually as concentrates.However, some of the individual components of these developers,especially of color developers, react with one another and at theconcentrations desired are not miscible. For these reasons theindividual components have been conveniently packaged in separatecompartments of a single package. In the separate compartments, theessential ingredients are desirably either liquid per se or in solutionso that mixing the ingredients into a complete developer involves littletime-consuming dissolution. The separate compartments have, for example,respectively contained benzyl alcohol, base plus buffering ingredients,hydroxylamine sulfate and an acidic solution of developing agent pulsesulfite.

We have found that even though the packaged components are all liquid,the mixing times involved in assuring complete dissolution of thecomponents in the ultimate developer were far in excess of that desiredby the trade. The excess mixing time frequently involves undesirableshutdown time for the processing machine. Such difficulty in assuringdissolution also often results in attempts to utilize the developerbefore complete dissolution and thereby causes quality control problemsand general inconsistency in processing characteristics. Since thesedifficulties result in substantial time loss and expense to both theprocessor and his customers and further result in dissatisfaction withthe photographic reproductions, investigations were undertaken to seekmethods and compositions which minimize the difficulties.

ln prepackaged photographic processing compositions, especially liquidconcentrates having separate compartments for keeping various essentialingredients from interacting, it has been considered necessary tocompartmentalize benzyl alcohol, which often is a desirable or necessarycomponent of such compositions, separately. This was apparently donebecause of the failure of benzyl alcohol to dissolve at the highconcentrations desired for liquid concentrates. We have unexpectedlyfound that even at the relatively low concentration in which benzylalcohol is employed in conventional photographic processing solutions,e.g., color developers, the benzyl alcohol has such low solubility tocause unnecessary time delays in mixing the components to form thedeveloper.

According to the present invention we have unexpectedly foundcompositions and methods which not only obviate the necessity ofpackaging benzyl alcohol separately from the other ingredients in liquidphotographic processing concentrates, but also facilitate thedissolution of benzyl alcohol to form the ready-to-use processingsolution, without detracting from the effectiveness of the overallprocessing characteristics of the solution. We have found that stable,concentrated dispersions, of benzyl alcohol in water are formed if theconcentrated composition contains water-soluble polymeric carbohydratesor polymeric amides, especially cellulose-based emulsifying agents. Wehave further found the extremely stable dispersions of benzyl alcoholpulse emulsifying agents in water are formed if the composition furthercontains ionic materials, for example, salts such as alkali metalsulfates, sulfites, phosphates, borates, citrates, etc. or othersubstances which are necessary or desirable in the intended processingsolution, such as hydroxylamine sulfate, etc. Surprisingly, the maximumamount of such salts that can be incorporated into the compositionsappears limited only by the solubility of the particular salt chosen.That is, although salts are not necessary to the formation of stabledispersions, very stable dispersions result even at high saltconcentration. For example, a disper sion containing containing awater/cellulose-based emulsifying agent weight ratio of about l/.00l to0.01, a water/benzyl alcohol weight ratio of about H to 25/ l and awater/salt ratio of l/.000l-0.33 presents a dispersion of outstandingstability. The benzyl alcohol may thus be incorporated into acompartment of the processing solution containing an aqueous solution ofother processing, e.g., developer, components and can be packaged inplastic, e.g., polyethylene containers. The shipping, handling, andpackaging costs for such processing compositions, therefore, can besubstantially decreased. Such compositions containing water, benzylalcohol, and the indicated emulsifying agents can also readily bediluted with more water and/or solutions containing other precessingcomponents with no appreciable oiling out" of the benzyl alcohol and iffound to substantially diminish the mixing time normally involved incombining separated components of liquid processing concentrates,especially in forming color developers.

In accordance with the present invention it is especially desirable toutilize a water/emulsifying agent weight ratio of about 1/0.0020.0 l. itis further desirable to maintain a water/benzyl alcohol weight ratio ofabout 1.] to 25/ l in the dispersion. in a highly efficacious embodimentof this invention, salts, especially hydroxylamine sulfate, are alsopresent such that the salt/water ratio is about 0.01-33/100, but limitedgenerally only by the solubility of the selected salt in aqueoussolution. Such compositions are found to be resistant to separation aswell as nonfoaming and have no appreciable detrimental effect when usedin the desired photographic processing solution, e.g., color developers.The minimum amount of cellulose-based emulsifier necessary may varysomewhat depending, inter alia, upon the particular emulsificationagent( s) selected, the amount of water present and the amount and typeof other components present, but there is desirably sufficientemulsifying agent to maintain a stable suspension of benzyl alcohol inthe concentrate.

it will, of course, be understood that the stable dispersions describedherein are those that are practically stable, i.e., dispersions which donot separate at all and those which do separate into apparently two ormore layers on long standing but which readily redisperse upon a mereinversion of the container or at most with moderate agitation.

Water-soluble polymeric carbohydrate emulsifying agents andwater-soluble polymeric amide emulsifying agents and water-solublecarbohydrate and polyamide derivatives are the only compositions foundwhich form stable dispersions of benzyl alcohol in water. Carbohydratecompositions which are effective are starch derivatives such as Ceron(Hercules Chemical Company), etc., Guar gums, for example, carboxymethylGuar, etc., and water-soluble cellulose-based emulsifying agents such ascellulose sulfates, cellulose acetate sulfates, low acetyl containingcellulose acetates, sodium algenate, sodium hydroxypropyl algenate,methyl cellulose ethyl cellulose phthalates, mixed ethers of cellulose,e.g., isopropylmethyl ethers, etc., and hydroxyethyl cellulosecompositions which result in dispersions of surprisingly outstandingeffectiveness. Polymeric amides of high effectiveness are the proteins,e.g., soya protein, lecithin and especially gelatin and emulsifyingagents which are water-soluble derivatives of gelatin, etc.

The silver halide developing agents especially useful in the developercompositions of the present invention are the pphenylenediaminecolor-developing agents well known in the art especially those formingnondiffusing dyes with phenolic and reactive methylene couplers. Thesedeveloping agents include p-phenylenediamine andN,N-dialkyl-p-phenylenediamines wherein the alkyl groups or the aromaticnucleus may be substituted, for example: N,N-diethyl-p-phenylenediaminemonohydrochloride, 2-amino-5- diethylaminotoluene monohydrochloride,4-amino-N-ethyl- N-[fl-methanesulfonamidoethyU-m-toluidine sesquisulfatemonohydrate, 4-amino-3-methyl-N-ethyl-N-[B-hydroxyethyll-anilinesulfate, 4-amino-3-(fl-methylsulfonamidoethyl)-N,N-diethylanilinehydrochloride, 4-amino- N ,N-diethyl-3 -(N'-methyl-,8-methylsulfonamido)-aniline hydrochloride and similarcolor-developing agents disclosed in U.S. Pat. Nos. 2,552,241 and2,566,271. Other useful pphenylenediamine developing agents aredisclosed in J .A.C.S. 73, 3,l-3,l25, (1951). Especially efi'ectivep-phenylenediamines are those containing at least onealkylsulfonamidoalkyl substitutent attached to the aromatic nucleus orto an amino nitrogen.

It is important that in prepackaged color developers containingp-phenylenediamine developing agents the solution containing thedeveloping agent be acidic to assist in the stabilization of thedeveloping agent and also to keep the developing agent in solution. ThepH is preferably less than about 4.However, the optimum pH will varydepending upon the particular developing agent in use, for example, when4- amino-N,N-diethyl-3-( N -methyl-B-rnethylsulfonamidoethyl anilinehydrochloride is used, it is desirable that the solution have a pH lessthan 1 particularly to keep the developing agent in solution in aconcentrate.

Other components can be prepackaged in the same compartment with thecolor-developing agents, for example, sulfite may be present inaccordance with the disclosure of U.S. Pat. Ser. No. 676,623 filed Oct.19, 1967, by Kanous and Bimmler and other substances useful in the colordevelopment reaction may be present, such as antifoggants, e.g.,benzotriazole, development restrainers, e.g., bromide and auxiliaryblack and white developing agents, such as the 3- pyrazolidone silverhalide developing agents, e.g., 4,4- dimethyl-l-phcnyl-S-pyrazolidone.However, it is usually desirable to only incorporate the sulfite anddeveloping agents as a simple aqueous solution with or without addedacid. The combined concentration of the sulfite and developing agent canvary widely. Since the developer package is designed for shipment andstorage, it is usually desirable to utilize the highest concentration ofingredients which will readily stay in acidic solution. More dilutesolutions can, of course, be utilized depending upon the individualcircumstances.

Packaging the benzyl alcohol in aqueous solutions of specificemulsifying agents generally is advantageous in packaging anycompositions which require or desirably contain compounds such as benzylalcohol, ultimately dispersed or dissolved in aqueous solution. Suchpackaging is significant in photographic silver halide developerpackages especially those which are to be utilized with well-known colorproducts having differently sensitized silver halide emulsion layerscontaining nondiffusing coupler compounds, for example, those havingsuperposed on a support, blue-, green-, and red-sensitized emulsionlayers containing yellow, magenta, and cyan dye-forming couplers,respectively. The advantages obtained according to the present inventionwill be appreciated in packaging developers for a wide variety of colorphotographic elements, i.e., multicolor systems containing superposedred, green, and blue light-sensitive silver halide emulsion layerscontaining a cyan-forming coupler (e.g., a phenolic compound), amagenta-forming coupler (e.g., a 5-pyrazolone compound) and ayellow-forming coupler (e.g., an open chain ketomethylene compound),respectively. Suitable nondifiusing couplers are disclosed in U.S. Pat.Nos. 2,956,876, 2,407,293, and 2,640,776.

The developer compositions when mixed and ready for use can anddesirably do contain the usual amounts of developing agent, sulfite andalkali as disclosed generally in the .lelley et al. U.S. Pat. No.2,322,027. According to this invention, packaged developer componentsadvantageously are separated to the extent that in compartmentscontaining developing agents, the sulfite concentration and the pH iscontrolled as indicated in U.S. Pat. Ser. No. 676,623, mentioned abovewith the benzyl alcohol dispersion included in one or more of thecompartments. Other components which may form part of the mixeddeveloper package, for example, additional sulfite, accelerators,complexing agents, buffers, e.g.,

citric acid-citrate, boric acid-borate, etc., are advantageouslycontained in the compartment conta ning the alkali, e.g., potassiumhydroxide, although placing selected addenda in other or separatecompartments may be desirable depending upon the particular ingredientchosen.

The packaged developer effectively may be a single package, for example,an outside container or cardboard box in which the developer componentsare compartmentalized. The compartments can be an integral part of theexterior packaging material but advantageously are, at least in part,merely bottles of, for example, glass and/or plastic enclosed in theoutside container. The choice of sizes and shapes of the bottles whichform the compartments can vary with the selected ingredients,concentrations desired, etc. Usually it is desirable to choose thebottle size, shape, etc. which will result in a total package of minimumsize and weight to minimize shipping and storage costs. As a result, itmay in some instances be desirable to place a single component type in aplurality of compartments, e.g., to conserve space.

The following examples are illustrative of the methods and compositionsof our invention:

EXAMPLE 1 A stable dispersion of benzyl alcohol in water is prepared inthe following manner:

50 mg. of Natrosol 250 H (a high-viscosity hydroxyethyl cellulosemarketed by Hercules Chemical Company) is added to 20 ml. of water. Themixture is stirred for about 1 hour. To this solution l2.6 ml. of benzylalcohol is added with stirring. After the addition is complete themixture is vigorously stirred. The resulting dispersion appears stableat room temperature.

EXAMPLE 2 The dispersion of example 1 is utilized as component A of afour'component liquid color developer. The remaining componentscontaining:

are combined with the benzyl alcohol dispersion and sufficient water tomake l liter of working solution. The solution appears completelyhomogeneous after only about one-half the time required for thedissolution of a similar developer devoid of hydroxyethyl cellulose. Thesolution functions effectively and consistently as a color developer forcolor print material having respectively superposed on a paper support,blue-, green-, and red-sensitized emulsion layers containing yellow,magenta, and cyan dye-forming couplers, respectively, which has beenexposed to a test pattern.

EXAMPLE 3 A dispersion of benzyl alcohol in a salt solution is preparedas follows:

2.1 g. of hydroxylamine sulfate is dissolved in 10 ml. of water. Toanother 10 ml. of water is added 50 mg. of hydroxyethyl cellulose(Natrosol 250 H). After a period of soaking and stirring for about 1hour the hydroxyethyl cellulose completely dissolves in the water. Thetwo solutions are mixed together and 12.6 ml. of benzyl alcohol is addedwith stirring. The mixture is then vigorously shaken.

The dispersion thus formed is stable for over 2 months at 120 F.

EXAMPLE 4 A dispersion of benzyl alcohol in salt solution is prepared asfollows:

2.l gms. of hydroxylamine sulfate is dissolved in 20 ml. of water. Tothis solution is added 50 mg. of hydroxyether cellulose (Natrosol 250H). After soaking and stirring for about 1 hour the hydroxyethylcellulose dissolves in the salt solution. To this solution benzylalcohol is added with rapid stirring.

The resultant dispersion is stable for over 2 months Storage t 29? FEXAMPLE 5 The dispersion of example 3 is utilized as component A of athree-component liquid concentrate color developer. The remainingcomponents containing:

monohydrate are readily combined with the benzyl alcohol dispersion andsufficient water to make 1 l. of working developer. The

developer appears completely homogeneous after about onehalf the timepreviously required for a composition containing no hydroxyethylcellulose.

The developer functions effectively and consistently when utilized withphotographic color print material as described above.

EXAMPLE 6 The procedure according to example 5 is followed except thatthe benzyl alcohol dispersion of example 4 is utilized in place of thedispersion of example 3. Comparable results are obtained.

EXAMPLE 7 A benzyl alcohol dispersion containing the following:

Water 20 cc. Hydroxylamine sulfate 2.l g. Natrosol 250 H 5.0 mg. Benzylalcohol 12.6 cc.

is prepared according to the procedure of example 3. The dispersion isstable except that after a period the dispersion appears to separateinto two layers. It is found that the dispersion is still stable butthat the dispersed complexes of benzyl alcohol and emulsifying agentmerely tend to be buoyant. Upon merely turning the container over, thedispersion appears homogeneous.

The dispersion functions effectively and is readily miscible with thephotographic color developer components B and C listed in example 5.

EXAMPLE 8 A benzyl alcohol dispersion containing the following:

Water 20 cc. Hydroxylamine sulfate 2.l g. Natrosol 250 H 200.0 mg.Benzyl alcohol l2.6 cc.

is prepared according to the procedure of example 4. The dispersion,although somewhat thick, appears stable and functions effectively andeasily mixes with the photographic developer components B and C listedin example 5.

EXAMPLE 9 A benzyl alcohol dispersion was prepared in the mannerindicated in example 3 except that Natrosol l H is utilized in place ofNatrosol 250 H. Comparable results are obtained both as to thedispersion itself and its effectiveness in a developer.

EXAMPLE 10 A benzyl alcohol dispersion is prepared in the mannerindicated in example 3 except that the moderately low-viscosityhydroxyethyl cellulose (Natrosol 250 G) is utilize in placed of thehigher viscosity analog. Comparable results are obtained both as to thedispersion itself and its effectiveness and ease of mixing with aphotographic color developer.

EXAMPLE 1 l A benzyl alcohol dispersion is prepared according to theprocedure outlined in example 3 except that carboxyethyl Guar isutilized in place of the Natrosol. The dispersion appears stable forperiods in excess of 1 week and functions well in photographicdevelopers.

Example 12 A benzyl alcohol dispersion is prepared according to theprocedure outlined in example 3 except that gelatin is utilized in placeof the Natrosol. The dispersion appears stable for periods in excess of1 week and functions well in photographic developers.

EXAMPLE 13 A benzyl alcohol dispersion is prepared according to theprocedure outlined in example 3 except that carboxymethyl cellulose isutilized in place of the Natrosol. The dispersion appears stable forperiods in excess of 1 week and functions well in photographicdevelopers.

EXAMPLE [4 A benzyl alcohol dispersion is prepared according to theprocedure outlined in example 3 except that carboxymethyl hydroxyethylcellulose is utilized in place of the Natrosol. The dispersion appearsstable for periods in excess of 1 week and functions well inphotographic developers.

The invention has been described in considerable detail with particularreference to preferred embodiments thereof, but it will be understoodthat variations and modifications can be effected within the spirit andscope of the invention as described hereinabove and as defined in theappended claims.

We claim:

1. A unitary packaged developer kit in which at least some of thedeveloper components are in separate compartments, said kit comprisingat least one compartment containing a composition comprising water,benzyl alcohol, and an emulsifying agent selected from the groupconsisting the water-soluble polymeric carbohydrate emulsifying agentsand watersoluble polymeric amide emulsifying agents and anothercompartment containing aqueous alkali and yet another compartmentcontaining a p-phenylenediamine developing agent.

2. The developer kit of claim 1 wherein the emulsifying agent is awater-soluble polymeric carbohydrate.

3. Tile developer kit of claim 1 wherein the emulsifying agent ishydroxyethyl cellulose and hydroxylamine sulfate is also present in saidfirst-mentioned compartment.

2. The developer kit of claim 1 wherein the emulsifying agent is awater-soluble polymeric carbohydrate.
 3. The developer kit of claim 1wherein the emulsifying agent is hydroxyethyl cellulose andhydroxylamine sulfate is also present in said first-mentionedcompartment.